Signal transmission via body conduction

ABSTRACT

Methods and apparatus for signal transmission via body conduction are disclosed herein. The assembly may be attached, adhered, or otherwise embedded into or upon a removable oral appliance to form a bearing aid assembly. Such an oral appliance may be a custom-made device which can enhance and/or optimize received data and/or audio signals for vibrational conduction to the user. Data and/or audio signals may be encoded and transmitted or received along or through the user&#39;s body to an oral appliance contained within or along the user&#39;s mouth. Alternatively, information may be transmitted between various other devices over the user&#39;s body aside from an oral appliance. The encoded signals may be decoded and the auditory signals may be transmitted via vibrational conductance to the user.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.12/398,463 filed Mar. 5, 2009, which claims priority to U.S. ProvisionalApplication Ser. No. 61/048,093, filed Apr. 25, 2008, the contents ofwhich are incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to methods and devices for near-field datacommunications. More particularly, the present invention relates tomethods and devices for near-field data communications utilizing thetransfer of signals via a human body to communicate with an oralappliance.

BACKGROUND OF THE INVENTION

With conventional near-field data communication devices using radiowaves, power consumption and size of the devices tend to be relativelylarge when utilizing wireless communication. Wireless communicationthrough the transmission of electromagnetic signals through air also hasother drawbacks such as the potential interference by stray signals anddifficulties in incorporating the necessary transmission and receptioncircuits into a device of a size that can be comfortably worn by theuser.

One application in particular is a hearing aid system utilizing two ormore components worn by a user at different locations over the user'sbody. During operation, it is generally desirable that one or morecommunication links be established between these components usingwireless technology. Although interconnecting these components by wiresor cables is possible, it may be undesirable to have wires passing alongdifferent parts of the body. Moreover, for certain devices which may beworn within the user's mouth, a wired device is generally undesirable.

Certain methods have been previously utilized for passing communicationsignals along or through the body of the user to enable the passing ofdata between different components. One method utilized an electrostaticfield induced in a human body to reduce power consumption and bytransferring high frequency modulated signals via the user's body and anearth ground. However, because ground is utilized as part of the signalpath, the size of the transmitter and receiver may be particularly smallto improve their wearability by the user but the distance traveled bythe communications signals becomes particularly shortened.

Yet other methods may utilize the transfer of signals between separatedevices using both transmission through an electric field induced overthe user's body in combination with signal transmission through the air.However, this and similar methods require the use of signal transmissionthrough an induced, electric field, and ground or still require the useof transmission through the air with its resultant power consumption anddevice form factors.

Accordingly, there is a need for near-field data communication devicesand methods which operate with reduced power consumption, have a formfactor which is suitably small for patient comfort, and which is able tocommunicate with devices configured for intra-oral placement and use.

SUMMARY OF THE INVENTION

An electronic and transducer device may be attached, adhered, orotherwise embedded into or upon a removable dental or oral appliance toform a hearing aid assembly. Such a removable oral appliance may be acustom-made device fabricated from a thermal forming process utilizing areplicate model of a dental structure obtained by conventional dentalimpression methods. The electronic and transducer assembly may receiveincoming sounds either directly or through a receiver to process andamplify the signals and transmit the processed sounds via a vibratingtransducer element coupled to a tooth or other bone structure, such asthe maxillary, mandibular, or palatine bone structure.

The assembly for transmitting vibrations via at least one tooth maygenerally comprise a housing having a shape which is conformable to atleast a portion of the at least one tooth, and an actuatable transducerdisposed within or upon the housing and in vibratory communication witha surface of the at least one tooth. Moreover, the transducer itself maybe a separate assembly from the electronics and may be positioned alonganother surface of the tooth, such as the occlusal surface, or evenattached to an implanted post or screw embedded into the underlyingbone.

In receiving and processing the various audio signals typically receivedby a user, various configurations of the oral appliance and processingof the received audio signals may be utilized to enhance and/or optimizethe conducted vibrations which are transmitted to the user. Forinstance, in configurations where one or more microphones are positionedwithin the user's mouth, filtering features such as Acoustic EchoCancellation (AEC) may be optionally utilized to eliminate or mitigateundesired sounds received by the microphones. In such a configuration,at least two intra-buccal microphones may be utilized to separate outdesired sounds (e.g., sounds received from outside the body such asspeech, music, etc.) from undesirable sounds (e.g., sounds resultingfrom chewing, swallowing, breathing, self speech, teeth grinding, etc.).

In utilizing a separate transmitter in communication with theelectronics and/or transducer assembly to transfer data and/or auditoryinformation, the transmitter may be located on or near the user's bodyin proximity to the oral appliance. In separating the transmitter,communication between the transmitter and oral appliance may be effectedby wireless communications utilizing radio waves, as described above.However, typical wireless communications assemblies require increasedpower levels. Thus, intra-device communications may alternatively beeffected by the transmission of signals through or along the user's bodyitself such as along the skin or through the underlying tissue.

An example of such intra-device linked communication through the user'sbody may utilize an extra-buccal transmitter assembly positioned behindone or both of the user's ear. The transmitter assembly may receive thedata and/or auditory information and convert this information todigitally encode and modulates the data and/or auditory information fortransmission over or through the skin and/or underlying tissue. Thereceiver assembly contained within the retaining portion of the oralappliance is specifically keyed to receive these digitally encodedsignals and to perform any error correction on the signal which is thenconverted to the audio signal for vibratory conductance to the user.

The transmitter assembly and receiver assembly in the retaining portionmay utilize an unbalanced data transmission where the transmitter sendsthe digitally encoded data and waits for a predetermined period of timeto receive any feedback signals or other information from the receiver,e.g., battery life, user-related data, etc., which may also be relayedfrom retaining portion back to the transmitting, assembly through oralong the user's skin or underlying tissue.

The transmitter assembly may receive any data and/or auditoryinformation or optional treatment algorithms which are digitally encodedvia an encoding assembly. The encoding assembly may be coupled to avariable gain amplifier which locks to a base level of noise and gatesthe noise level accordingly in the encoded signal, which is thentransmitted to a first region of the body (e.g., behind the ear, alongthe wrist, etc.) via a single electrode coupled to the skin surface. Theelectrode may be coupled directly to the skin surface or through acoupling interface such as a gel or other conductive medium.Alternatively, the electrode may be maintained in proximity to the skinsurface with an intermediate protective layer or held at a distance suchthat no direct contact is made between the electrode and the skinsurface and coupling occurs via capacitive coupling. The singleelectrode may eliminate the need for use of a reference voltage and mayalso eliminate the need for transmission through earth ground.Alternatively, additional electrodes (e.g., two electrodes) may be usedto enhance signal transmission and/or reception if so desired but is notnecessary for use.

Once the encoded signal is transmitted through electrode, thetransmission signal may be transmitted through or along the skin or itmay be transmitted through or along the underlying tissue. Thetransmitted signals may pass through the user's whole body or through aportion of the skin and/or underlying tissue where the power fortransmitting the signal ranges in the sub-milliwatt level to a fewmilliwatts of power, e.g., less than 10 milliwatts.

Optionally and/or additionally, the encoding assembly may furtherinclude a scrambler which may scramble the encoded signal prior totransmission to encrypt the signal. The scrambler may transpose, invert,or otherwise further encode the signal to make the transmittedinformation unintelligible at the receiver assembly to prevent otherunintended persons from picking up and decoding the transmittedinformation from the user's body. A receiving electrode which is also incontact with the user's body at a second region (e.g., within the user'smouth along, the tooth or teeth, in contact with the inner cheek, aregion of the gums, a portion of the tongue, etc.) may receive theencoded signals and transmit them to an amplifier within the receivingassembly located within or along retaining portion. As the interior ofthe user's mouth is typically wet with saliva, the reception of theencoded signals may be particularly effective. The encoded and amplifiedsignals may be decoded via decoding assembly and the decoded data and/orauditory information may be received by a transducer assembly which maythen transmit the data and/or auditory information through vibratoryconductance into the underlying third region of the user's body such asthe underlying tooth or teeth.

In other variations, a pair of transmitting assemblies may be utilizedbehind each ear of user. In this manner, each assembly may communicatewith a single receiving assembly along the retaining portion or with twoor more receivers along both retaining portions. Because the user's bodyis utilized as a conductive transmission link, the transmitter assemblymay be placed at various locations over the body. For example, atransmitter assembly may be configured as a watch and worn on the user'swrist or as a PDA, music player, etc., which may be worn on the usersbelt or other clothing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates the dentition of a patient's teeth and one variationof a hearing aid device which is removably placed upon or against thepatient's tooth or teeth as a removable oral appliance.

FIG. 2A illustrates a perspective view of the lower teeth showing oneexemplary location for placement of the removable oral appliance hearingaid device.

FIG. 2B illustrates another variation of the removable oral appliance inthe form of an appliance which is placed over an entire row of teeth inthe manner of a mouthguard.

FIG. 2C illustrates another variation of the removable oral appliancewhich is supported by an arch.

FIG. 2D illustrates another variation of an oral appliance configured asa mouthguard.

FIG. 3 illustrates a detail perspective view of the oral appliancepositioned upon the patient's teeth utilizable in combination with atransmitting assembly external to the mouth and wearable by the patientin another variation of the device.

FIG. 4 shows an illustrative configuration of one variation of theindividual components of the oral appliance device having an externaltransmitting assembly with a receiving and transducer assembly withinthe mouth.

FIG. 5 shows an illustrative configuration of another variation of thedevice in which the entire assembly is contained by the oral appliancewithin the user's mouth.

FIG. 6 illustrates an example of how multiple oral appliance hearing aidassemblies or transducers may be placed on multiple teeth throughout thepatient's mouth.

FIG. 7 illustrates another variation of a removable oral appliancesupported by an arch and having a microphone unit integrated within thearch.

FIG. 8A illustrates another variation of the removable oral appliancesupported by a connecting member which may be positioned along, thelingual or buccal surfaces of a patient's row of teeth.

FIGS. 8B to 8E show examples of various cross-sections of the connectingsupport member of the appliance of FIG. 8A.

FIG. 9 shows yet another variation illustrating at least one microphoneand optionally additional microphone units positioned around the user'smouth and in wireless communication with the electronics and/ortransducer assembly.

FIG. 10 illustrates yet another example of a configuration forpositioning multiple transducers and/or processing units along apatient's dentition.

FIG. 11A illustrates another variation on the configuration forpositioning multiple transducers and/or processors supported via anarched connector.

FIG. 11B illustrates another variation on the configuration utilizing aconnecting member positioned along the lingual surfaces of a patient'sdentition.

FIG. 12 shows an extra-buccal transmitter assembly positioned behind oneor both of the user's ear and communicating with a receiving assemblycontained within or along a receiving portion of an oral appliance.

FIG. 13 schematically illustrates an example of the signal transmissionthrough or along the user's body.

FIGS. 14A and 1413 shows an example of a digital encoding scheme forencoding data and/or auditory information to be transmitted along orthrough the user's body.

FIG. 15 shows a pair of transmitting assemblies placed behind each earof the user communicating with multiple receiver assemblies.

FIG. 16 shows an example of various locations where a transmitterassembly may be positioned over the user's body for communication withthe oral appliance.

DETAILED DESCRIPTION OF THE INVENTION

An electronic and transducer device may be attached, adhered, orotherwise embedded into or upon a removable oral appliance or other oraldevice to form a hearing aid assembly. Such an oral appliance may be acustom-made device fabricated from a thermal forming process utilizing areplicate model of a dental structure obtained by conventional dentalimpression methods. The electronic and transducer assembly may receiveincoming sounds either directly or through a receiver to process andamplify the signals and transmit the processed sounds via a vibratingtransducer element coupled to a tooth or other bone structure, such asthe maxillary, mandibular, or palatine bone structure.

As shown in FIG. 1, a patient's mouth and dentition 10 is illustratedshowing one possible location for removably attaching hearing aidassembly 14 upon or against at least one tooth, such as a molar 12. Thepatient's tongue TG and palate PG are also illustrated for reference. Anelectronics and/or transducer assembly 16 may be attached, adhered, orotherwise embedded into or upon the assembly 14, as described below infurther detail.

FIG. 2A shows a perspective view of the patient's lower dentitionillustrating the hearing aid assembly 14 comprising a removable oralappliance 18 and the electronics and/or transducer assembly 16positioned along a side surface of the assembly 14. In this variation,oral appliance 18 may be fitted upon two molars 12 within tooth engagingchannel 20 defined by oral appliance 18 for stability upon the patient'steeth, although in other variations, a single molar or tooth may beutilized. Alternatively, more than two molars may be utilized for theoral appliance 18 to be attached upon or over. Moreover, electronicsand/or transducer assembly 16 is shown positioned upon a side surface oforal appliance 18 such that the assembly 16 is aligned along a buccalsurface of the tooth 12; however, other surfaces such as the lingualsurface of the tooth 12 and other positions may also be utilized. Thefigures are illustrative of variations and are not intended, to belimiting; accordingly, other configurations and shapes for oralappliance 18 are intended to be included herein.

FIG. 2B shows another variation of a removable oral appliance in theform of an appliance 15 which is placed over an entire row of teeth inthe manner of a mouthguard. In this variation, appliance 15 may beconfigured to cover an entire bottom row of teeth or alternatively anentire upper row of teeth. In additional variations, rather thancovering the entire rows of teeth, a majority of the row of teeth may beinstead be covered by appliance 15. Assembly 16 may be positioned alongone or more portions of the oral appliance 15.

FIG. 2C shows yet another variation of an oral appliance 17 having anarched configuration. In this appliance, one or more tooth retainingportions 21, 23, which in this variation may be placed along the upperrow of teeth, may be supported by an arch 19 which may lie adjacent oralong the palate of the user. As shown, electronics and/or transducerassembly 16 may be positioned along one or more portions of the toothretaining portions 21, 23. Moreover, although the variation shownillustrates an arch 19 which may cover only as portion of the palate ofthe user, other variations may be configured to have an arch whichcovers the entire palate of the user.

FIG. 2D illustrates yet another variation of an oral appliance in theform of a mouthguard or retainer 25 which may be inserted and removedeasily from the user's mouth. Such a mouthguard or retainer 25 may beused in sports where conventional mouthguards are worn; however,mouthguard or retainer 25 having assembly 16 integrated therein may beutilized by persons, hearing impaired or otherwise, who may simply holdthe mouthguard or retainer 25 via grooves or channels 26 between theirteeth for receiving instructions remotely and communicating over adistance.

Generally, the volume of electronics and/or transducer assembly 16 maybe minimized so as to be unobtrusive and as comfortable to the user whenplaced in the mouth. Although the size may be varied, a volume ofassembly 16 may be less than 800 cubic millimeters. This volume is, ofcourse, illustrative and not limiting as size and volume of assembly 16and may be varied accordingly between different users.

Moreover, removable oral appliance 18 may be fabricated from variouspolymeric or a combination of polymeric and metallic materials using anynumber of methods, such as computer-aided machining processes usingcomputer numerical control (CNC) systems or three-dimensional printingprocesses, e.g., stereolithography apparatus (SLA), selective lasersintering (SLS), and/or other similar processes utilizingthree-dimensional geometry of the patient's dentition, which may beobtained via any number of techniques. Such techniques may include useof scanned dentition using intra-oral scanners such as laser, whitelight, ultrasound, mechanical three-dimensional touch scanners, magneticresonance imaging (MRI), computed tomography (CT), other opticalmethods, etc.

In forming the removable oral appliance 18, the appliance 18 may beoptionally formed such that it is molded to fit over the dentition andat least a portion of the adjacent gingival tissue to inhibit the entryof food, fluids, and other debris into the oral appliance 18 and betweenthe transducer assembly and tooth surface. Moreover, the greater surfacearea of the oral appliance 18 may facilitate the placement andconfiguration of the assembly 16 onto the appliance 18.

Additionally, the removable oral appliance 18 may be optionallyfabricated to have a shrinkage factor such that when placed onto thedentition, oral appliance 18 may be configured to securely grab onto thetooth or teeth as the appliance 18 may have a resulting size slightlysmaller than the scanned tooth or teeth upon which the appliance 18 wasformed. The fitting may result in a secure interference fit between theappliance 18 and underlying dentition.

In one variation, with assembly 14 positioned upon the teeth, as shownin FIG. 3, an extra-buccal transmitter assembly 22 located outside thepatient's mouth may be utilized to receive auditory signals forprocessing and transmission via a wireless signal 24 to the electronicsand/or transducer assembly 16 positioned within the patient's mouth,which may then process and transmit the processed auditory signals viavibratory conductance to the underlying tooth and consequently to thepatient's inner ear.

The transmitter assembly 22, as described in further detail below, maycontain a microphone assembly as well as a transmitter assembly and maybe configured in any number of shapes and forms worn by the user, suchas a watch, necklace, lapel, phone, belt-mounted device, etc.

FIG. 4 illustrates a schematic representation of one variation ofhearing aid assembly 14 utilizing an extra-buccal transmitter assembly22, which may generally comprise microphone or microphone array 30(referred to “microphone 30” for simplicity) for receiving sounds andwhich is electrically connected to processor 32 for processing theauditory signals. Processor 32 may be connected electrically totransmitter 34 for transmitting the processed signals to the electronicsand/or transducer assembly 16 disposed upon or adjacent to the user'steeth. The microphone 30 and processor 32 may be configured to detectand process auditory signals in any practicable range, but may beconfigured in one variation to detect auditory signals ranging from,e.g., 250 Hertz to 20,000 Hertz.

With respect to microphone 30, a variety of various microphone systemsmay be utilized. For instance, microphone 30 may be a digital, analog,and/or directional type microphone. Such various types of microphonesmay be interchangeably configured to be utilized with the assembly, ifso desired. Moreover, various configurations and methods for utilizingmultiple microphones within the user's mouth may also be utilized, asfurther described below.

Power supply 36 may be connected to each of the components intransmitter assembly 22 to provide power thereto. The transmittersignals 24 may be in any wireless form utilizing, e.g., radio frequency,ultrasound, microwave, Blue Tooth® (BLUETOOTH SIG, INC., Bellevue,Wash.), etc. for transmission to assembly 16. Assembly 22 may alsooptionally include one or more input controls 28 that a user maymanipulate to adjust various acoustic parameters of the electronicsand/or transducer assembly 16, such as acoustic focusing, volumecontrol, filtration, muting, frequency optimization, sound adjustments,and tone adjustments, etc.

The signals transmitted 24 by transmitter 34 may be received byelectronics and/or transducer assembly 16 via receiver 38, which may beconnected to an internal processor for additional processing of thereceived signals. The received signals may be communicated to transducer40, which may vibrate correspondingly against a surface of the tooth toconduct the vibratory signals through the tooth and bone andsubsequently to the middle ear to facilitate hearing of the user.Transducer 40 may be configured as any number of different vibratorymechanisms. For instance, in one variation, transducer 40 may be anelectromagnetically actuated transducer. In other variations, transducer40 may be in the form of a piezoelectric crystal having a range ofvibratory frequencies, e.g., between 250 Hz to 20,000 Hz.

Power supply 42 may also be included with assembly 16 to provide powerto the receiver, transducer, and/or processor, if also included.Although power supply 42 may be a simple battery, replaceable orpermanent, other variations may include a power supply 42 which ischarged by inductance via an external charger. Additionally, powersupply 42 may alternatively be charged via direct coupling to analternating current (AC) or direct current (DC) source. Other variationsmay include a power supply 42 which is charged via a mechanicalmechanism, such as an internal pendulum or slidable electricalinductance charger as known in the art, which is actuated via, e.g.,motions of the jaw and/or movement for translating the mechanical motioninto stored electrical energy for charging power supply 42.

In another variation of assembly 16, rather than utilizing anextra-buccal transmitter, hearing aid assembly 50 may be configured asan independent assembly contained entirely within the user's mouth, asshown in FIG. 5. Accordingly, assembly 50 may include at least oneinternal microphone 52 in communication with an on-board processor 54.Internal microphone 52 may comprise any number of different types ofmicrophones, as described below in further detail. At least oneprocessor 54 may be used to process any received auditory signals forfiltering and/or amplifying the signals and transmitting them totransducer 56, which is in vibratory contact against the tooth surface.Power supply 58, as described above, may also be included withinassembly 50 for providing power to each of the components of assembly 50as necessary.

In order to transmit the vibrations corresponding to the receivedauditory signals efficiently and with minimal loss to the tooth orteeth, secure mechanical contact between the transducer and the tooth isideally maintained to ensure efficient vibratory communication.Accordingly, any number of mechanisms may be utilized to maintain thisvibratory communication.

For any of the variations described above, they may be utilized as asingle device or in combination with any other variation herein, aspracticable, to achieve the desired hearing level in the user. Moreover,more than one oral appliance device and electronics and/or transducerassemblies may be utilized at any one time. For example, FIG. 6illustrates one example where multiple transducer assemblies 60, 62, 64,66 may be placed on multiple teeth. Although shown on the lower row ofteeth, multiple assemblies may alternatively be positioned and locatedalong, the upper row of teeth or bath rows as well. Moreover, each ofthe assemblies may be configured to transmit vibrations within a uniformfrequency range. Alternatively in other variations, different assembliesmay be configured to vibrate within overlapping or non-overlappingfrequency ranges between each assembly. As mentioned above, eachtransducer 60, 62, 64, 66 can be programmed or preset for a differentfrequency response such that each transducer may be optimized for adifferent frequency response and/or transmission to deliver a relativelyhigh-fidelity sound to the user.

Moreover, each of the different transducers 60, 62, 64, 66 can also beprogrammed to vibrate in a manner which indicates the directionality ofsound received by the microphone worn by the user. For example,different transducers positioned at different locations within theuser's mouth can vibrate in a specified manner by providing sound orvibrational queues to inform the user which direction a sound wasdetected relative to an orientation of the user, as described in furtherdetail below. For instance, a first, transducer located, on a user'sleft tooth, can be programmed to vibrate for sound detected originatingfrom the user's left side. Similarly, a second transducer located, e.g.,on a user's right tooth, can be programmed to vibrate for sound detectedoriginating from the user's right side. Other variations and queues maybe utilized as these examples are intended to be illustrative ofpotential variations.

FIG. 7 illustrates another variation 70 which utilizes an arch 19connecting one or more tooth retaining portions 21, 23, as describedabove. However, in this variation, the microphone unit 74 may beintegrated within or upon the arch 19 separated from the transducerassembly 72. One or more wires 76 routed through arch 19 mayelectrically connect the microphone unit 74 to the assembly 72.Alternatively, rather than utilizing a wire 76, microphone unit 74 andassembly 72 may be wirelessly coupled to one another, as describedabove.

FIG. 8A shows another variation 80 which utilizes a connecting member 82which may be positioned along the lingual or buccal surfaces of apatient's row of teeth to connect one or more tooth retaining portions21, 23. Connecting member 82 may be fabricated from any number ofnontoxic materials, such stainless steel, Nickel, Platinum, etc. andaffixed or secured 84, 86 to each respective retaining portions 21, 23.Moreover, connecting member 82 may be shaped to be as non-obtrusive tothe user as possible. Accordingly, connecting member 82 may beconfigured to have a relatively low-profile for placement directlyagainst the lingual or buccal teeth surfaces. The cross-sectional areaof connecting member 82 may be configured in any number of shapes solong, as the resulting geometry is non-obtrusive to the user. FIG. 8Billustrates one variation of the cross-sectional area which may beconfigured as a square or rectangle 90. FIG. 8C illustrates anotherconnecting member geometry configured as a semi-circle 92 where the flatportion may be placed against the teeth surfaces. FIGS. 8D and 8Eillustrate other alternative shapes such as an elliptical shape 94 andcircular shape 96. These variations are intended to be illustrative andnot limiting as other shapes and geometries, as practicable, areintended to be included within this disclosure.

In yet another variation for separating the microphone from thetransducer assembly, FIG. 9 illustrates another variation where at leastone microphone 102 (or optionally any number of additional microphones104, 106) may be positioned within the mouth of the user whilephysically separated from the electronics and/or transducer assembly100. In this manlier, the one or optionally more microphones 102, 104,106 may be wirelessly or by wire coupled to the electronics and/ortransducer assembly 100 in a manner which attenuates or eliminatesfeedback from the transducer, also described in further detail below.

In utilizing multiple transducers and/or processing units, severalfeatures may be incorporated with the oral appliance(s) to effect anynumber of enhancements to the quality of the conducted vibratory signalsand/or to emulate various perceptual features to the user to correlateauditory signals received by a user for transmitting, these signals viasound conduction through teeth or bone structures in and/or around themouth.

As illustrated in FIG. 10, another variation for positioning one or moretransducers and/or processors is shown. In this instance generally, atleast two microphones may be positioned respectively along toothretaining portions 21, 23, e.g., outer microphone 110 positioned along abuccal surface of retaining portion 23 and inner microphone 112positioned along a lingual surface of retaining portion 21. The one ormore microphones 110, 112 may receive the auditory signals which areprocessed and ultimately transmitted through sound conductance via oneor more transducers 114, 116, 118, one or more of which may be tuned toactuate only along certain discrete frequencies, as described in furtherdetail below.

Moreover, the one or more transducers 114, 116, 118 may be positionedalong respective retaining portions 21, 23 and configured to emulatedirectionality of audio signals received by the user to provide a senseof direction with respect to conducted audio signals. Additionally, oneor more processors 120, 124 may also be provided along one or bothretaining portions 21, 23 to process received audio signals, e.g., totranslate the audio signals into vibrations suitable for conduction tothe user, as well as other providing for other functional features.Furthermore, an optional processor 122 may also be provided along one orboth retaining portions 21, 23 for interfacing and/or receiving wirelesssignals from other external devices such as an input control, asdescribed above, or other wireless devices.

FIG. 11A illustrates another configuration utilizing an arch 130 similarto the configuration shown in FIG. 7 for connecting the multipletransducers and processors positioned along tooth retaining portions 21,23. FIG. 11B illustrates yet another configuration utilizing aconnecting member 132 positioned against the lingual surfaces of theuser's teeth, similar to the configuration shown in FIG. 8A, also forconnecting the multiple transducers and processors positioned alongtooth retaining portions 21, 23.

In configurations particularly where the one or more microphones arepositioned within the user's mouth, filtering features such as AcousticEcho Cancellation (AEC) may be optionally utilized to eliminate ormitigate undesired sounds received by the microphones. AEC algorithmsare well utilized and are typically used to anticipate the signal whichmay re-enter the transmission path from the microphone and cancel it outby digitally sampling an initial received signal to form a referencesignal. Generally, the received signal is produced by the transducer andany reverberant signal which may be picked up again by the microphone isagain digitally sampled to form an echo signal. The reference and echosignals may be compared such that the two signals are summed ideally at180° out of phase to result in a null signal, thereby cancelling theecho. Examples of AEC as well as other variations for processing audiosignals with respect to the assembly are shown and described in greaterdetail in U.S. patent application Ser. No. 11/672,239, filed Feb. 7,2007, which is incorporated herein by reference in its entirety.

In utilizing a separate transmitter in communication with theelectronics and/or transducer assembly 16 to transfer data and/orauditory information for treatment, the transmitter may be located on ornear the user's body in proximity to the oral appliance. In separatingthe transmitter, communication between the transmitter and oralappliance may be effected by wireless communications utilizing radiowaves, as described above. However, typical wireless communicationsassemblies require increased power levels. Thus, intra-devicecommunications may alternatively be effected by the transmission ofsignals through or along the user's body itself such as along the skinor through the underlying tissue.

An example of such intra-device linked, communication through the user'sbody 140 is illustrated in the profile view of FIG. 12, which shows anextra-buccal transmitter assembly 142 positioned, in this example,behind, one or both of the user's ear. The transmitter assembly 142 mayreceive the data and/or auditory information and convert thisinformation to digitally encode and modulates the data and/or auditoryinformation for transmission over or through the skin and/or underlyingtissue, as indicated by the transmitted control signals 144. Thereceiver assembly contained within retaining portion 21 of the oralappliance, shown positioned within the mouth of the user 140 andretained upon the tooth or teeth, is specifically keyed to receive thesedigitally encoded signals 144 and to perform any error correction on thesignal 144 which is then converted to the audio signal for vibratoryconductance to the user 140.

The digitally encoded signal 144 transmitted by transmitter assembly 142may generally comprise a wideband carrier signal having a shaped noiseprofile which is injected or transmitted into or along the user's body140 utilizing a single band at a single frequency ranging anywherebetween 100 kHz to 1 GHz. The signal frequency may also exceed 1 GHz,however, higher frequencies may typically require higher power levelswith accompanying higher levels of noise and increase loss of thesignal.

Moreover, the transmitter assembly 142 and receiver assembly inretaining portion 21 may utilize an imbalanced data transmission wherethe transmitter 142 sends the digitally encoded data and waits for apredetermined period of time to receive any feedback signals 146 orother information from the receiver, e.g., battery life, user-relateddata, etc., which may also be relayed from retaining portion 21 back tothe transmitting assembly 142 through or along the user's skin orunderlying tissue.

The feedback signal 146 may also be utilized to readjust levels by thereceiver (e.g., shaped noise) to change the levels transmitted by thetransmitter assembly 142 to optimize changes in the levels of injectednoise. For instance, when changes in received auditory signals or soundsoccur such as a high level of external noise source approaching, theuser 140, the receiver may send feedback signals 146 along or throughthe user's body to the transmitter 142 which then readjusts the injectedshaped noise level. Moreover, feedback signals 146 may be utilized toswitch modes if added noise from external noise sources at certain areasof frequency bands are higher than acceptable levels.

The transmitter assembly 150 and receiving assembly 160 located withinor along retaining portion 21 is illustrated schematically in FIG. 13 toshow an example of the signal transmission through or along the user'sbody. Transmitter assembly 150 may receive any data and/or auditoryinformation or optional treatment algorithms 152 which are digitallyencoded via an encoding assembly 154, such as processor 32 describedabove running an encoding algorithm. The encoding assembly 154 may becoupled to a variable gain amplifier 156 which locks to a base level ofnoise and gates the noise level accordingly in the encoded signal, whichis then transmitted to a first region of the body 172 (e.g., behind theear, along the wrist, etc.) via a single electrode 158 coupled to theskin surface. Electrode 158 may be coupled directly to the skin surface172 or through a coupling interface such as a gel or other conductivemedium. Alternatively, electrode 158 may be maintained in proximity tothe skin surface 172 with an intermediate protective layer or held at adistance such that no direct contact is made between the electrode 158and the skin surface 172 and coupling occurs via capacitive coupling.The single electrode 158 may eliminate the need for use of a referencevoltage and may also eliminate the need for transmission through earthground. Alternatively, additional electrodes (e.g., two electrodes) maybe used to enhance signal transmission and/or reception if so desiredbut is not necessary for use.

Once the encoded signal is transmitted through electrode 158, thetransmission signal may be transmitted through or along the skin, asindicated by transmission signal 178, or it may be transmitted throughor along the underlying tissue, as indicated by transmission signal 180.The transmitted signals 178, 180 may pass through the user's whole bodyor through a portion of the skin and/or underlying tissue where thepower for transmitting the signal ranges in the sub-milliwatt level to afew milliwatts of power, e.g., less than 10 milliwatts.

Optionally and/or additionally, the encoding assembly 154 may furtherinclude a scrambler contained within assembly 154 or separate therefromwhich may scramble the encoded signal prior to transmission to encryptthe signal. The scrambler may transpose, invert, or otherwise furtherencode the signal to make the transmitted information unintelligible atthe receiver assembly to prevent other unintended persons from pickingup and decoding the transmitted information from the user's body.

With encoded signals transmitted from electrode 158 at the firstlocation 172, a receiving electrode 166 which is also in contact withthe user's body at a second region 174 (e.g., within the user's mouthalong the tooth or teeth, in contact with the inner cheek, a region ofthe gums, a portion of the tongue, etc.) may receive the encoded signalsand transmit them to an amplifier 164 within receiving assembly 160located within or along retaining portion 21. As the interior of theuser's mouth is typically wet with saliva, the reception of the encodedsignals 178, 180 may be particularly effective.

The encoded and amplified signals may be decoded via decoding assembly162, e.g., a processor contained within retaining portion 21, and thedecoded data and/or auditory information may be received by a transducerassembly 168 which may then transmit the data and/or auditoryinformation through vibratory conductance 170 into the underlying thirdregion 176 of the user's body such as the underlying tooth or teeth, asdescribed above. If the received information were scrambled, decodingassembly 162 may further include a descrambler contained within orseparate therefrom to descramble the received information. As mentionedabove, the any feedback or return signals may be similarly transmittedthrough electrode 166 and into the second region 174 for transmissionthrough or along the user's skin, as indicated by return signal 182, orthrough the underlying tissue, as indicated by return signals 184.

In digitally encoding the data and/or auditory information or treatmentsignal 152, a number of encoding algorithms may be employed. One exampleof an encoding algorithm which may be utilized is a Winchester encodingalgorithm, as known in the art. As schematically illustrated in FIG.14A, Winchester encoding utilizes a minimum level of noise whereby abase level is considered “0” and changes to the static coding or peaklevels of noise are considered “1”. Thus, a first encoded bit 190 for anoise level going from “A” to “B” may be assigned to a transmitted bitvalue of “0”, as indicated by the chart of FIG. 14B. A second encodedbit 192 may be assigned a value of “1” for increased noise levels, asindicated from “B” to “A” where for any increased noise levels, thenoise level is peaked and the data and/or auditory information to betransmitted is digitally encoded accordingly. The noise level is shapedto have an area consistent with sufficient transmission and eachfrequency band is different. In this manner, the data and/or auditoryinformation 152 may be encoded for transmission along or through theuser's body to the receiver assembly. The receiving assembly may thusreceive this encoded signal and decode the signal correspondingly, e.g.,for vibratory transmission to the user.

In other variations, a pair of transmitting assemblies 142, 142′ may beutilized behind each ear of user 140, as shown in FIG. 15. In thismanner, each assembly 142, 142′ may communicate with a single receivingassembly along retaining portion 21 or with two or more receivers alongboth retaining portions 21, 23. The example shown illustrates avariation where transmitting assemblies 142, 142′ may communicate 144,144′ with respective receiver assemblies in respective retainingportions 21, 23. Likewise, feedback or return signals 146, 146′ may betransmitted from the receiver back to each respective transmitter aswell. If two or more electrodes are utilized, each electrode may bepositioned on opposite sides of the user's mouth along both retainingportions 21, 23 as well.

Because the user's body is utilized as a conductive transmission link,the transmitter assembly may be placed at various locations over thebody. For example, a transmitter assembly may be configured as a watch200 and worn on the user's wrist such that conducted signals 208 aretransmitted through the user's arm 204 to the receiving assemblies inreceiving portion 21 and/or 23. Likewise, the transmitter assembly 202may be configured as a PDA, music player, etc., which may be worn on theuser's belt or other clothing. The conducted signals 210 may betransmitted along the user's torso 206 where the transmitter 202 iscapacitively coupled to the user's underlying skin surface.

The applications of the devices and methods discussed above are notlimited to specific treatments. Moreover, such devices and methods maybe applied to other treatment sites within the body. Modification of theabove-described assemblies and methods for carrying out the invention,combinations between different variations as practicable, and variationsof aspects of the invention that are obvious to those of skill in theart are intended to be within the scope of the claims.

What is claimed is:
 1. A data and audio signal transmission system forcommunication over a body of a user, comprising: a transmitter assemblyin electrical communication through a single electrode adapted to beelectrically coupled with a skin surface at a first region of the bodyand where the transmitter assembly is adapted to transmit a data signalover or through the skin surface or underlying tissue of the body; areceiver assembly electrically coupled with the skin surface at a secondregion of the body and adapted to receive the data signal transmittedthrough the skin surface or underlying tissue of the body by thetransmitter assembly; and a transducer assembly positioned within oralong a housing which is configured for placement within a mouth of theuser, wherein the transducer assembly is in electrical communicationwith the receiver assembly and includes a transducer configured tocontact at least one tooth and vibrationally conduct the data signalthrough the at least one tooth.